Drugs, alcohol, and now coffee! I’ve used a variety of substances to self medicate while in a depressed mood. A few years ago I cut out cannabis, and I stay away from using alcohol when I’m down, but I have no limits with coffee. It seems like I can drink as much as I want whenever I want and it doesn’t create the same problems it does when my mood is better.
Recently I’ve found green tea to be amazing and without the jitteryness of coffee. There are many kinds to try, all quite different!
Adding onto this, I didn’t enjoy green tea until I started brewing it gong fu style with loose leaves. Teabags are acceptable for black tea but completely ruin green imo.
It’s also worth noting that there’s a noticable flavor and taste difference between different types of green (for example, I dislike the popular dragonwell, but love maofeng/mountain green tips). There’s also a gulf of difference between Chinese and Japanese green teas, due to the processing. Usually Chinese tea is pan/wok/hot air fried, leading to a more nutty and complex profile, whereas Japanese greens tend to be steamed, leading to a more vegetal taste.
I also really like matcha, if you can afford the initial investment. It’s definitely unique and can be an acquired taste. I really like the ippodo Sayaka/Horai, since it doesn’t have a very strong umami taste, which can be off putting for people new to matcha.
Edit: and yes, there is actual science backing up your interpretation of green tea being less jittery. The L-theanine, an amino acid unique to green tea and a few mushroom varieties, has a balancing effect when paired with caffeine.